Stator Structure of Axial Flux Motor

This application claims priority to U.S. Provisional Application Ser. No. 63/647,085, filed May 14, 2024 and China Application Serial Number 202411665180.5, filed Nov. 20, 2024, the disclosures of which are incorporated herein by reference in their entireties.

The present disclosure relates to a motor structure, and more particularly to a winding structure of an axial flux motor stator.

Motors are components configured to convert electrical energy into mechanical energy and have been widely used in daily life. The current axial flux motor uses distributed winding, and the conductors are routed along the circumferential slots in the stator slots according to the corresponding magnetic pole positions. In order to ensure that the conductor arrangements can effectively fill the space in the slot and improve the slot fill factor, the two conductors in adjacent slots must be swapped up and down in the axial direction for the protrusions before routing to the next magnetic pole. This makes it difficult for each conductor to be further assembled into a complete winding after being bent, and the overall winding needs to be formed using complex winding methods and equipment.

The present disclosure provides a stator structure of an axial flux motor to deal with the needs of the prior art problems.

In one or more embodiments, a stator structure of an axial flux motor includes a plurality of magnetic poles having a plurality of magnetic pole positions and a plurality of level-positions. The conductors are routed from one magnetic pole position to another magnetic pole position of the magnetic pole positions and wound through the level-positions respectively to form a plurality of windings. Each conductor climbs to a higher level-position while being routed from a magnetic pole to a next magnetic pole of the magnetic poles after passing through one of the lowest level-positions of the level-positions until climbing to the highest level-positions of the level-positions. The conductors comprise a first conductor and a second conductor, and all portions of the first conductor and the second conductor that have relative positions remain unchanged in an axial direction.

In one or more embodiments, each conductor includes a plurality of inner diameter protrusions located in an internal space surrounding an axis of the soft magnetic material body, and two halves of each inner diameter protrusion are at two positions that are aligned with two immediately-adjacent level-positions in the axial direction respectively.

In one or more embodiments, each conductor includes a plurality of outer diameter protrusions exposed outside an outer sidewall of the soft magnetic material body, and two halves of each outer diameter protrusion are at two positions that are aligned with two immediately-adjacent level-positions in the axial direction respectively.

In one or more embodiments, each conductor includes a plurality of inner diameter protrusions located in an internal space surrounding an axis of the soft magnetic material body, and each inner diameter protrusion of the second conductor is at least partially located above a corresponding inner diameter protrusion of the first conductor in the axial direction.

In one or more embodiments, each conductor includes a plurality of outer diameter protrusions exposed outside an outer sidewall of the soft magnetic material body, and each outer diameter protrusion of the second conductor is at least partially located above a corresponding outer diameter protrusion of the first conductor in the axial direction.

In one or more embodiments, each conductor is formed by bending a continuous conductor, or includes a plurality of assembled or welded conductors.

In one or more embodiments, each conductor is wound around the soft magnetic material body in a spiral or star-shaped arrangement.

In one or more embodiments, each conductor includes a plurality of inner diameter protrusions located in an internal space surrounding an axis of the soft magnetic material body, and a half of each inner diameter protrusion of the second conductor is located above an immediately-adjacent half of a corresponding inner diameter protrusion of the first conductor in the axial direction.

In one or more embodiments, each conductor includes a plurality of outer diameter protrusions exposed outside an outer sidewall of the soft magnetic material body, and a half of each outer diameter protrusion of the second conductor is located above an immediately-adjacent half of a corresponding outer diameter protrusion of the first conductor in the axial direction.

In one or more embodiments, the stator structure further includes a soft magnetic material body having the plurality of magnetic poles and a plurality of slots, each slot including the level-positions arranged in the axial direction.

In one or more embodiments, each conductor includes a plurality of inner diameter protrusions, a plurality of receiving portions and a plurality of outer diameter protrusions, the receiving portions are disposed in the slots, the inner diameter protrusions are disposed in an internal space surrounding an axis of the soft magnetic material body, and the outer diameter protrusions are exposed outside an outer sidewall of the soft magnetic material body.

In one or more embodiments, the conductors are inserted in the slots and partially protruded from the soft magnetic material body toward both an internal space surrounding an axis and an outer sidewall of the soft magnetic material body.

In one or more embodiments, each conductor includes a plurality of inner diameter protrusions located in an internal space surrounding an axis of the soft magnetic material body, and two halves of each inner diameter protrusion are at two positions that are aligned with two immediately-adjacent level-positions in the axial direction respectively.

In one or more embodiments, each conductor includes a plurality of outer diameter protrusions exposed outside an outer sidewall of the soft magnetic material body, and two halves of each outer diameter protrusion are at two positions that are aligned with two immediately-adjacent level-positions in the axial direction respectively.

In one or more embodiments, each conductor includes a plurality of inner diameter protrusions, a plurality of receiving portions and a plurality of outer diameter protrusions, the receiving portions are disposed in the slots, the inner diameter protrusions are disposed in an internal space surrounding an axis of the soft magnetic material body, and the outer diameter protrusions are exposed outside an outer sidewall of the soft magnetic material body.

In sum, the stator structure of the axial flux motor disclosed herein has its conductor formed into a climbing structure arranged in a spiral or star-shaped arrangement in the circumferential direction. Each time when each conductor is routed from one magnetic pole position to the next magnetic pole position, the conductor protruding from the slot climbs to a higher level-position, and continue to climb toward the highest level-positions until reaching the highest level-position in the slots. This conductor structure allows the relative positions of the upper and lower conductors to remain positions relation unchanged while winding different strands of conductors, thereby avoiding up and down staggering. This structure allows each conductor to be assembled into a complete winding in a simple manner after being formed or bent, and deals with various deficiencies in conventional solutions. After each conductor climbs to the highest level-position of the slots, the conductors are connected in series to the next conductor through the connecting section, and the same structure continues to climb from the lowest level-position to the highest level-position.

It is to be understood that both the foregoing general description and the following detailed description are by examples, and are intended to provide further explanation of the disclosure as claimed.

Reference will now be made in detail to the present embodiments of the disclosure, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.

Reference is made to, a stator structureof an axial flux motor includes a soft magnetic material bodyand a plurality of conductors. The soft magnetic material bodyhas a plurality of magnetic poles and a plurality of slots. In some embodiments of the present disclosure, the soft magnetic material bodyincludes 24 slotsfor a plurality of conductorsto pass through in a distributed winding manner to form a plurality of windings. Taking a three-phase axial flux motor as an example, 24 slotsare divided by 3 (phases) to formmagnetic poles. In other words, a section including three slots forms a magnetic pole. In some embodiments of the present disclosure, the soft magnetic material bodyis composed of a plurality of silicon steel sheetsstacked in an axial direction AD or in a radial direction. In some embodiments of the present disclosure, the soft magnetic material bodyis composed of soft magnetic composite (SMC). In some embodiments of the present disclosure, each slotincludes a plurality of level-positions (L, L, L˜Ln) arranged in the axial direction AD, and a single conductor only occupies a single level-position while being routed through the slot.

Reference is made to, a conductoris configured to pass through the slotof the soft magnetic material bodyto form a winding. In some embodiments of the present disclosure, the conductorincludes a plurality of inner diameter protrusions, a plurality of receiving portions, and a plurality of outer diameter protrusion. Each receiving portionis located in a corresponding slot of the soft magnetic material bodyand connected between the corresponding inner diameter protrusionand the outer diameter protrusion. The soft magnetic material bodyis generally a hollow columnar structure. The inner diameter protrusionsare located in an internal spaceof the soft magnetic material body, and the outer diameter protrusionsare exposed outside an outer sidewallof the soft magnetic material body(referring to), the internal spaceis located between the soft magnetic material bodyand an axis, i.e., the soft magnetic material bodysurrounds the axis to form the internal space. In some embodiments of the present disclosure, each conductorincludes a plurality of inner diameter protrusionslocated in the internal spacesurrounding the axis of the soft magnetic material body(refer to), and each inner diameter protrusionhas two halves (,) at a level-position difference in the axial direction AD (refer to, the halfis one level-position higher than the half). That is, two halves (,) of each inner diameter protrusionare at two positions that are aligned with two immediately-adjacent level-positions in the axial direction AD respectively. In some embodiments of the present disclosure, each conductorincludes a plurality of outer diameter protrusionsexposed outside the outer sidewallof the soft magnetic material body(refer to), and each outer diameter protrusionhas two halves (,) located at a level-position difference in the axial direction AD (refer to, the halfis one level-position higher than the half). That is, two halves,of each outer diameter protrusionare at two positions that are aligned with two immediately-adjacent level-positions in the axial direction AD respectively. In some embodiments of the present disclosure, after each conductorpasses through one of the lowest level-positions among the level-positions (refer to, e.g., the bottom endis located at the level-position L), each conductoris routed from one magnetic pole position to another magnetic pole position, climbing to the higher level-positions (such as L), until climbing through one of the highest level-positions among the level-positions (refer to, i.e., the top endis located at level-position Ln). In some embodiments of the present disclosure, each conductoris formed by bending a continuous linear conductor. In other embodiments of the present disclosure, each conductorincludes a plurality of assembled or welded linear conductors.

Reference is made to, and this figure shows the two conductors (/) inpassing through the adjacent slots of the soft magnetic material body. In order to clearly show the positional relationship of the two conductors (,), the soft magnetic material bodyis not shown. After the two conductors (,) go through one of the lowest level-positions of the slots (i.e., the bottom endsandare at the lowest level-position), they climb up to the higher level-positions among the level-positions each time they are routed to the next magnetic pole position until climbing passes through one of the highest level-positions among the level-positions (i.e., the top endandare at the highest level-position). In some embodiments of the invention, each inner diameter protrusionof the conductoris at least partially located above the corresponding inner diameter protrusionof the conductorin the axial direction AD (e.g., the halfof the conductoris located above the halfof the conductor). In some embodiments of the present disclosure, each outer diameter protrusionof the conductoris at least partially located above the corresponding outer diameter protrusionof the conductorin the axial direction AD (e.g., the halfof the conductoris located between the conductorAbove half). In some embodiments of the invention, the halfof each inner diameter protrusionof the conductoris located above the halfof the immediately-adjacent inner diameter protrusionof the conductorin the axial direction AD. In some embodiments of the invention, the halfof each outer diameter protrusionof the conductoris above the halfof the immediately adjacent outer diameter protrusionof the conductorin the axial direction AD. In some embodiments of the present disclosure. When the two conductors (,) are wound around the soft magnetic material body, all the portions of the conductors (,) protruding from all the slots of the soft magnetic material bodyhave their relative positions remain unchanged in the axial direction AD during the entire winding process. That is, the relative positions of the upper and lower level-positions for all inner diameter protrusions and outer diameter protrusions of the conductors (,) remain their positions relation unchanged. For example, the relative positions of the outer diameter protrusions of the two conductors remain unchanged, and/or the relative positions of the inner diameter protrusions of the two conductors remain unchanged. In some embodiments of the present disclosure, the two conductors (,) are arranged in a spiral or star-shaped arrangement while being wound around the soft magnetic material bodyto further avoid interlacing of upper and lower conductors.

Reference is made to, and the windingincludes multiple conductors (,,,) connected with one another. After the bottom endof the conductoris routed through one of the lowest level-positions (e.g., L) in the corresponding slot, it climbs to a higher level-position in the slot each time when it crosses to be wound on the next magnetic pole position, until the top endof the conductorclimbs through one of the highest level-positions in the slots. Similarly, after the bottom endof the conductoris routed through one of the lowest level-positions (e.g., L) in the corresponding slot, it climbs to a higher level-position in the slot every time when it crosses to be wound on the next magnetic pole position, until the top endof the conductorclimbs through one of the highest level-positions in the slots. The two conductors (,) are connected in series with a connecting section. Then, after the bottom endof the conductorcrosses one of the lowest level-positions (e.g., L) in the corresponding slot, it climbs to a higher level-position in the slot each time when it crosses to be wound on the next magnetic pole position, until the top endof the conductorclimbs through one of the highest level-positions in the slots. The two conductors (,) are connected in series with a connecting section. After the bottom endof the conductoris routed through one of the lowest level-positions (e.g., L) in the corresponding slot, it climbs to a higher level-position in the slot each time when it crosses to be wound on the next magnetic pole position, until the top endof the conductorclimbs through one of the highest level-positions in the slot. The two conductors (,) are connected in series with a connecting section. Multiple conductors (,,,) are connected in series through the connecting sectionto form a winding. Taking a three-phase axial flux motor as an example, the other two-phase windings (i.e., the U-phase and V-phase windings) are also formed in a similar manner and occupy the remaining slotsof the soft magnetic material body, which will not be described again.

Reference is made to, and this figure shows a coreless stator structureof an axial flux motor with a plurality of conductors, and the coreless stator structureis not equipped with a soft magnetic material body, e.g., the soft magnetic material bodyin, to achieve a simple and neat structure. Without the soft magnetic material body, the coreless stator structurestill has a plurality of magnetic poles equipped with a plurality of magnetic pole positions and level-positions, and the conductorshas similar features as the conductors (,,,,) illustrated in. Each conductorclimbs to a higher level-position while being routed from a magnetic pole to a next magnetic pole after passing through one of the lowest level-positions until climbing to the highest level-positions. The portions of the conductors have relative positions remain unchanged in an axial direction.

In sum, the stator structure of the axial flux motor disclosed herein has its conductor formed into a climbing structure arranged in a spiral or star-shaped arrangement in the circumferential direction. Each time when each conductor is routed from one magnetic pole position to the next magnetic pole position, the conductor protruding from the slot climbs to a higher level-position, and continue to climb toward the highest level-position until reaching the highest level-position in the slot. This conductor structure allows the relative positions of the upper and lower conductors to remain positions relation unchanged while winding different strands of conductors, thereby avoiding up and down staggering. This structure allows each conductor to be assembled into a complete winding in a simple manner after being formed or bent, and deals with various deficiencies in conventional solutions. After each conductor climbs to the highest level-position of the slot, the conductors are connected in series to the next conductor through the connecting section, and the same structure continues to climb from the lowest level-position to the highest level-position.

Although the present disclosure has been described in considerable detail with reference to certain embodiments thereof, other embodiments are possible. Therefore, the spirit and scope of the appended claims should not be limited to the description of the embodiments contained herein.

It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present disclosure without departing from the scope or spirit of the disclosure. In view of the foregoing, it is intended that the present disclosure cover modifications and variations of this disclosure provided they fall within the scope of the following claims.